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Application of peridynamics to dynamic fracture process analysis of rock-like materials
Published in Ömer Aydan, Takashi Ito, Takafumi Seiki, Katsumi Kamemura, Naoki Iwata, 2019 Rock Dynamics Summit, 2019
D. Fukuda, J. Kodama, Y. Fujii, S.H. Cho, H. Liu, A. Chan
Successful modeling of complex dynamic fracture process in rocks due to external impact loads, such as percussive hammer drilling and explosive blasting, is very important yet challenging task. In many existing computational mechanics approaches based on such as finite element method (FEM) including eXtended FEM, the target governing equation includes the spacial derivative of stress tensor and this causes the crack tip singularity of strain/stress. Silling (Silling, 2000,) developed the peridynamics (PD) as a new paradigm of continuum mechanics based on non-local theory. The spacial derivative of stress tensor is replaced by integration of force (state) in the PD which is characterized by length-scale parameter “horizon” and the crack is a part of the solution and not a part of the problem. Furthermore, no representation of the crack topology is needed. This feature makes the PD theory ideal for handling the problems with complex fracture process with relative ease. In fact, crack initiation/propagation/branching/coalescence even for 3D dynamics fracture problems can be easily modeled in the PD. At present, there have been three types of peridynamics formulations developed, namely, the bond-based PD (BB-PD), ordinary state-based PD (OSB-PD) and non-ordinary state-based PD (NOSB-PD). However, the PD is still a relatively new theory and the number of its applications to rock dynamics problems has been very limited.
Modeling microstructure of materials by using peridynamics
Published in C. Guedes Soares, Y. Garbatov, Progress in the Analysis and Design of Marine Structures, 2017
N. Zhu, D. De Meo, S. Oterkus, E. Oterkus
ABSTRACT: Polycrystalline materials are commonly used in many different fields including marine structures. In some cases, microstructure can be very effective, especially in the fracture process. Therefore, it is important to perform a detailed analysis at microscopic (grain) level to have a better understanding of the fracture behavior of these materials. As a new continuum mechanics formulation, peridynamics, can be very useful due to its various advantages with respect to some other traditional techniques including linear elastic fracture mechanics, cohesive zone model and extended finite element method. Hence, in this study, peridynamic analysis of cubic polycrystalline materials is presented under plane strain conditions. Depending on the grain boundary strength, intergranular and/or transgranular fracture modes are obtained. Moreover, for weak grain boundaries, microcrack shielding phenomenon is successfully captured.
Accurate numerical integration in 3D meshless peridynamic models
Published in Alphose Zingoni, Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems, 2022
U. Galvanetto, F. Scabbia, M. Zaccariotto
Peridynamics is a non-local continuum theory devised to naturally model fracture in solid bodies (Silling 2000). The equations in the peridynamic formulation are based on integrals over spheric domains, named “neighborhoods”, with a radius δ. Near the boundaries of the body some neighborhoods are not complete, which leads to undesired stiffness fluctuations, the so-called surface effect, and problems in imposing the boundary conditions. These issues can be solved as shown in the works of Scabbia et al. (2021) and Scabbia et al. (2022a).
Peridynamic modeling of freeze-thaw damage in concrete structures
Published in Mechanics of Advanced Materials and Structures, 2023
Pan Wu, Yunpeng Liu, Xuhao Peng, Ziguang Chen
Peridynamics (PD) is a non-local theory, first proposed by Silling in 2000 [31]. This theory describes the movement of the material points by solving spatial integral equations, completely solving the problem caused by discontinuities [31–33]. Peridynamics has a natural theoretical advantage in simulating discontinuities in the deformation field. Since its proposal, it has been quickly applied in many fields and successfully solved some great challenges [34–38]. It is worth noting that the PD method, as a nonlcoal method, suffers from the problem of high computational cost, which hinders its application in practical engineering. Coupling PD with the local models, such as FEM, to obtain a numerical model with the advantages of two computational techniques provides a method to deal with this issue [39–41]. Another promising way is a convolution-based method [42], which can reduce the computational complexity of PD models from O(N2) to O(Nlog2N), with N being the total number of discretization nodes.
Metaheuristic-based crack detection in beam-type structures using peridynamics theory: A comparative study
Published in Mechanics of Advanced Materials and Structures, 2023
Ehsan Afshari, Farshid Mossaiby, Taha Bakhshpoori
Peridynamics is a nonlocal generalization of classical continuum mechanics that was first introduced by Silling [30]. In 2005, Silling and Askari [31] proposed a meshless discretization of the theory. Since its presentation, several works based on this method have been published, modeling various physical phenomena involving crack nucleation and propagation. Dynamic, (quasi-) static and various multi-physics problems have been approached by the scientists using PD [32–34]. In PD, the integro-differential governing equations are employed; therefore, in contrast to the standard theory of solid mechanics, PD can be applied for modeling of bodies with discontinuities such as cracks. The body is placed in a spatial region and it is assumed to be composed of a number of material points. Any material point x in body interacts via bonds with other material points (neighbors) that are in the limited distance δ from it. The neighborhood region, represented by is defined as:
Numerical simulation of the effect of water-decoupling charge blasting on reservoir permeability enhancement
Published in Geomatics, Natural Hazards and Risk, 2022
Wen Wang, Wei Wang, Wei Yuan, Genmao Zhou, Xiaoqiao Feng, Xuanyu Liang
Blast-induced fractures are a key factor in reservoir permeability enhancement, to model blast-induced fractures, various computational methods have been developed and applied (Gharehdash et al. 2021a, 2021b). For examples, Zhu and Zhao (2021) have presented a peridynamics-based computational approach for modelling blast-induced rock fractures, which is shown to capture reasonably well the plastic material failure surrounding the borehole as well as the tensile cracks in both radial and circumferential directions. Gharehdash et al. (2020a, 2020b) found that smoothed particle hydrodynamics (SPH) method can predict qualitatively and quantitatively the blast-induced fractures, and calculate the permeability of blasting rock, with convincing results. Baranowski et al. (2020) have used the Johnson-Holmquist II (JH-2) model with parameters for a dolomite rock to simulate blast-induced rock fragmentation and compared it with the experimental results, the JH-2 method has a good application prospect.